注意下列加粗字的读音：
缚一人（ ）酒酣（ ）诣王（ ）曷为（ ）
fù；hān；yì；hé
He has been in high spirits, for pieces of exciting news came to him __________.
A．one after another
B．one by one
C．little by little
D．step by step
励磁系统输出的励磁电压必须保证顶值电压倍数要求，保证顶值电压倍数要求所对应的机端电压最小为（）。
A.80%
B.85%
C.90%
